This research is directed towards increasing our understanding of normal and abnormal erythrocyte and leukocyte metabolism and towards elucidating the pathogenesis of both hereditary and acquired hemolytic anemias. The enzymatic behavior and constituents of separated red cells and white cells are being investigated in hemolysates and homogenates. Metabolic studies of the pentose phosphate pathway and recycling in intact cells are being performed with radioactive labeled compounds utilizing our ionization chamber method. Our objectives are to extend our knowledge of pyruvate kinase deficiency and other enzyme deficiency hemolytic anemias with particular references to genetic polymorphism, to define new enzymopenic hemolytic disorders, to enlarge our understanding of certain acquired hemolytic anemias, and to utilize as metabolic models the red cell and white cell, since they are easily sampled and may reflect metabolic abnormalities or changes occurring in other less accessible tissues due to a congenital or hereditary metabolic defect, systemic disease, or administration of drugs, hormones, or vitamins. These studies should provide a better basis for our understanding of normal and abnormal red cell and white cell metabolism and lead to better diagnosis and therapy of clinical disease.